In one treatment for infertility, biological material such as gametes, embryos and/or zygotes are deposited into the reproductive tract of a mammalian female. Application Ser. No. 08/053,150, now U.S. Pat. No. 5,374,247 describes a technique for delivering a substance, such as biological material, to the fallopian tube utilizing an everting catheter and a transfer or delivery catheter.
It is also known to deposit biological material in the uterus. The uterus comprises opposed walls which are either in contact or in closely adjacent confronting relationship.
A transfer catheter can be used to deposit a substance in the uterus. It would be desirable to use an everting catheter to place the transfer catheter in the uterus because of the atraumatic nature of the everting catheter. A known everting catheter includes an elongated outer tubular body having an outer body lumen, an opening leading from the outer body lumen, an elongated inner tubular body movable longitudinally in the outer body lumen and having an inner body lumen, and an everting element coupled to the outer body and the inner body. Consequently, with movement of the inner body longitudinally in the outer body lumen, the everting element can be everted and inverted.
Everting of the everting catheter within the uterus urges the opposed walls of the uterus apart to form a chamber. The transfer catheter can then be inserted into the everting catheter to place the distal end of the transfer catheter at or closely adjacent the distal end of the everted everting element. However, the distal end of the transfer catheter may be occluded by being pressed into the endometrial tissue and delivery of the substance through the transfer catheter when in this position may be difficult if the distal opening of the transfer catheter is occluded by the everting element. The consequence of this occlusion is that the deposition of biological material, which may comprise only a few cells, will not occur if the biological material remains in the lumen of the inner body.
It is also possible to use an everting catheter to place a sampling instrument within a location, such as the urinary bladder, in the human body. In this event, it is desirable to know the location of the sampling instrument and to have the sampling instrument held in a stable condition.